S-91781A574 1/4"-20 x 4 1/2" ASME B18.6.3 Stainless Steel Slotted Flat Head Screws
Stainless Steel Slotted Flat Head Screws
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Basic Information
Head Parameters
Dimensions
Thread Parameters
Tip & Drive Parameters
Material & Strength
Temperature & Environment
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Key Features & Benefits at a Glance
- Superior corrosion resistance with 18-8 Stainless Steel construction and passivated finish, ensuring long-term reliability in harsh environments.
- High tensile strength of 80,000 psi and Rockwell B80 hardness for dependable performance in demanding heavy-duty applications.
- Precise 82° countersink angle and flat head design provides a flush, secure fit that minimizes protrusion and reduces snagging risks.
- Coarse UNC threads and Class 2A fit enable quick, easy installation and reliable holding power in various materials.
- Partial threading offers optimal grip length control, allowing for focused clamping force where it's needed most.
- Compliance with ASME B18.6.3 guarantees dimensional accuracy and interchangeability, reducing assembly errors.
- RoHS 3 and REACH compliance ensures environmental safety and regulatory adherence for global industrial use.
Professional Applications & Engineering Value
This 1/4"-20 UNC Flat Head Slotted Screw is engineered to address common industrial challenges such as material fatigue and environmental degradation. The 18-8 Stainless Steel material, combined with a passivated finish, provides exceptional resistance to rust and chemical exposure, making it ideal for machinery, marine equipment, and outdoor structures. Its coarse thread design ensures rapid installation and strong retention in wood, metal, and plastic assemblies, while the flat head with 82° countersink allows for a smooth, flush surface—critical in applications where aerodynamics or safety are priorities. With a tensile strength of 80,000 psi, it supports high-stress applications without failure, reducing maintenance needs and downtime in industrial settings.
Specification Summary & Compliance
This screw adheres to Class 2A thread fit and UNC coarse threading standards for consistent performance. It meets ASME B18.6.3 specifications for dimensional accuracy and is compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) regulations, ensuring it is free from hazardous substances and suitable for international industrial use.
